Army Sgt. Maj. Robert Bowman died of a rare cancer his widow believes developed after he was exposed to a toxin in Iraq. (Bowman family)

In June 2011, Army Master Sgt. Rob Bowman began feeling “off,” experiencing night sweats and registering a low-grade fever.

He didn’t think much of it. But when symptoms persisted, Bowman, about to report to the Sergeants Major Academy, went to a doctor. He didn’t want to start school — the path to his goal of becoming a command sergeant major — sick.

The diagnosis was devastating. Rather than the flu he suspected, Bowman had cholangiocarcinoma, a rare cancer of the bile ducts.

The Iraq veteran, then 42, began chemotherapy and forged on, achieving the rank of sergeant major. But on Jan. 13, 2013, he lost his battle with cancer, leaving behind a wife and four daughters.

How the powerful, healthy soldier whose awards included a Bronze Star with combat “V” developed the illness is unknown. He didn’t have the associated gene mutation, nor did he smoke.

Doctors suspect an environmental toxin. And Bowman’s wife, Coleen, is convinced that toxin — or whatever it was that sickened her husband — is in Iraq. On June 11, she spoke to a Pentagon panel about her husband’s fight to live, and why she believes other troops have been similarly sickened.

“There are other diseases — cancer, gastrointestinal problems, tumors — that troops are getting and no one is talking about them,” she said before a meeting of the Defense Health Board’s public health subcommittee, which has been tasked by the Defense Department to review evidence of deployment-related lung diseases.

But Bowman wanted panel members to be aware of other exposure-related illnesses in Iraq and Afghanistan.

More than 3,500 troops have registered deployment-related pulmonary concerns with Burn Pits 360, an advocacy group for troops with respiratory illnesses, but little is known about those with other diseases such as cancer, Crohn’s disease and fibrous tumors.

Few studies have been done on the relationship between certain types of cancer and combat deployments. The Millennium Cohort Study, a vast collaborative health review between DoD and the Veterans Affairs Department that began in 2001 and is expected to last through 2022, is looking at the long-term health of many Iraq and Afghanistan veterans.

A 2009 Uniformed Services University of the Health Sciences study showed active-duty personnel generally have lower overall rates of cancer than civilians but have higher rates of breast and prostate cancer. That study, however, looked at all troops, not just those who deployed.

The DHA panel also heard from Peter Sullivan, whose son Tom, a Marine sergeant, died from complications of severe inflammatory bowel problems and an enlarged heart but was treated by military doctors as having a psychosomatic — rather than physical — disorder.

“Treating patients presenting with respiratory symptoms competently means taking into account all aspects of their health. ... The subcommittee should consider the illnesses and symptoms that tend to accompany the respiratory illnesses that are the focus of its review,” Paul Sullivan told the panel.

He and his wife founded the Washington, D.C.-based Sergeant Sullivan Center to bring together vets’ groups, health care providers and researchers to improve care for veterans with various deployment-related illnesses, not just those tied to pulmonary problems.

Coleen Bowman said her husband’s lungs were blackened with soot and riddled with nodules when he died. But it was his cancer that made her an advocate.

“A third of Rob’s platoon is sick ... Cancer, Crohn’s disease, liver problems, brain bleeds, birth defects. Rob’s company commander was just diagnosed with cancer. I believe they were exposed to something,” she said.

For its review of pulmonary health among Iraq and Afghanistan veterans, the DHA panel has interviewed researchers, physicians and other specialists in addition to soliciting public comment.

Retired Public Health Service Rear Adm. Clifford Lane assured the Sullivans, Bowman, Rosie Torres of Burn Pits 360 and others that the panel is taking a broad view.

“I don’t think there is any question in our minds that there are soldiers who are deployed who come back with pulmonary problems,” Lane said. “What we’re trying to get to is can we identify what causes them, whether we can screen for these things.”

The group will report its findings and recommendations on future research and surveillance to the Defense Health Board. If accepted, they will go to the undersecretary of defense for personnel and readiness, who requested the review.

Tom Sullivan’s brother Dan told the panel that the Pentagon must do more to educate troops and physicians about the known health risks of deployment, as well as conditions that may not normally be associated with combat.

“It’s difficult ... to get information on the known health risks of deployment,” he said. “People are dying, and they are dying without information.”